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51.
Matthew T. Eddy Marina Belenky Astrid C. Sivertsen Robert G. Griffin Judith Herzfeld 《Journal of biomolecular NMR》2013,57(2):129-139
The power of nuclear magnetic resonance spectroscopy derives from its site-specific access to chemical, structural and dynamic information. However, the corresponding multiplicity of interactions can be difficult to tease apart. Complimentary approaches involve spectral editing on the one hand and selective isotope substitution on the other. Here we present a new “redox” approach to the latter: acetate is chosen as the sole carbon source for the extreme oxidation numbers of its two carbons. Consistent with conventional anabolic pathways for the amino acids, [1-13C] acetate does not label α carbons, labels other aliphatic carbons and the aromatic carbons very selectively, and labels the carboxyl carbons heavily. The benefits of this labeling scheme are exemplified by magic angle spinning spectra of microcrystalline immunoglobulin binding protein G (GB1): the elimination of most J-couplings and one- and two-bond dipolar couplings provides narrow signals and long-range, intra- and inter-residue, recoupling essential for distance constraints. Inverse redox labeling, from [2-13C] acetate, is also expected to be useful: although it retains one-bond couplings in the sidechains, the removal of CA–CO coupling in the backbone should improve the resolution of NCACX spectra. 相似文献
52.
Erawan Borkham-Kamphorst Eddy van de Leur Henning W. Zimmermann Karlin Raja Karlmark Lidia Tihaa Ute Haas Frank Tacke Thorsten Berger Tak W. Mak Ralf Weiskirchen 《生物化学与生物物理学报:疾病的分子基础》2013,1832(5):660-673
Lipocalin-2 is expressed under pernicious conditions such as intoxication, infection, inflammation and other forms of cellular stress. Experimental liver injury induces rapid and sustained LCN2 production by injured hepatocytes. However, the precise biological function of LCN2 in liver is still unknown. In this study, LCN2?/? mice were exposed to short term application of CCl4, lipopolysaccharide and Concanavalin A, or subjected to bile duct ligation. Subsequent injuries were assessed by liver function analysis, qRT-PCR for chemokine and cytokine expression, liver tissue Western blot, histology and TUNEL assay. Serum LCN2 levels from patients suffering from liver disease were assessed and evaluated. Acute CCl4 intoxication showed increased liver damage in LCN2?/? mice indicated by higher levels of aminotransferases, and increased expression of inflammatory cytokines and chemokines such as IL-1β, IL-6, TNF-α and MCP-1/CCL2, resulting in sustained activation of STAT1, STAT3 and JNK pathways. Hepatocytes of LCN2?/? mice showed lipid droplet accumulation and increased apoptosis. Hepatocyte apoptosis was confirmed in the Concanavalin A and lipopolysaccharide models. In chronic models (4 weeks bile duct ligation or 8 weeks CCl4 application), LCN2?/? mice showed slightly increased fibrosis compared to controls. Interestingly, serum LCN2 levels in diseased human livers were significantly higher compared to controls, but no differences were observed between cirrhotic and non-cirrhotic patients. Upregulation of LCN2 is a reliable indicator of liver damage and has significant hepato-protective effect in acute liver injury. LCN2 levels provide no correlation to the degree of liver fibrosis but show significant positive correlation to inflammation instead. 相似文献
53.
Oylum Erkus Victor CL de Jager Maciej Spus Ingrid J van Alen-Boerrigter Irma MH van Rijswijck Lucie Hazelwood Patrick WM Janssen Sacha AFT van Hijum Michiel Kleerebezem Eddy J Smid 《The ISME journal》2013,7(11):2126-2136
Maintenance of a high degree of biodiversity in homogeneous environments is poorly understood. A complex cheese starter culture with a long history of use was characterized as a model system to study simple microbial communities. Eight distinct genetic lineages were identified, encompassing two species: Lactococcus lactis and Leuconostoc mesenteroides. The genetic lineages were found to be collections of strains with variable plasmid content and phage sensitivities. Kill-the-winner hypothesis explaining the suppression of the fittest strains by density-dependent phage predation was operational at the strain level. This prevents the eradication of entire genetic lineages from the community during propagation regimes (back-slopping), stabilizing the genetic heterogeneity in the starter culture against environmental uncertainty. 相似文献
54.
Territory Availability at Different Spatial Scales does not Affect Fighting Investment in Males of the Lycaenid Butterfly Strymon mulucha
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Cibele P. S. Ferreira Luana P. Cerqueira Alexandre Uezu Eddy J. F. Oliveira Paulo E. C. Peixoto 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(10):798-806
In territorial species, rivals investment in fights over territories may increase when the availability of suitable areas for defense is low. This should occur because low territory availability may increase the costs to maintain and acquire territories. Although such process occurs in small spatial scales (local scale), territory availability in larger scales (regional scale) may also affect fighting investment, as losers should incur additional dispersing costs to find new territories. In this study, we used males of the hilltopping butterfly Strymon mulucha to evaluate the hypothesis that males should invest more in territorial fights when the costs to find new territories are higher (both at local and at regional scale). We timed male–male contests for territories located in 12 hilltops and measured male density per territory in each hilltop (local scale). We also quantified the distance between hilltops containing suitable areas for territories (regional scale). Male–male contests lasted 21 s on average, and copulations did not occur during the observations. The duration of contests was unrelated to the male density per territory or to the distance among hilltops, indicating that the investment in fights was unaffected by the availability of territorial sites, independent of the spatial scale. As male–male contests in S. mulucha are longer than the mean contest duration in other butterfly species and mating is extremely rare, we suggest that the value of each territory may be high enough to favor males that always invest as much as possible in contests. 相似文献
55.
56.
Gong Chang Cheng Ziliang Yang Yaping Shen Jun Zhu Yingying Ling Li Lin Wanyi Yu Zhigang Li Zhihua Tan Weige Zheng Chushan Zheng Wenbo Zhong Jiajie Zhang Xiang Zeng Yunjie Liu Qiang Huang R. Stephanie Komorowski Andrzej L. Yang Eddy S. Bertucci François Ricci Francesco Orlandi Armando Franceschini Gianluca Takabe Kazuaki Klimberg Suzanne Ishii Naohiro Toss Angela Tan Mona P. Cherian Mathew A. Song Erwei 《中国科学:生命科学英文版》2022,65(11):2205-2217
Science China Life Sciences - Patients with hormone receptor (HR)-positive tumors breast cancer usually experience a relatively low pathological complete response (pCR) to neoadjuvant chemotherapy... 相似文献
57.
Wordsworth S Buchanan J Regan R Davison V Smith K Dyer S Campbell C Blair E Maher E Taylor J Knight SJ 《Genomic Medicine》2007,1(1-2):35-45
Array based comparative genomic hybridisation (aCGH) is a powerful technique for detecting clinically relevant genome imbalance
and can offer 40 to > 1000 times the resolution of karyotyping. Indeed, idiopathic learning disability (ILD) studies suggest
that a genome-wide aCGH approach makes 10–15% more diagnoses involving genome imbalance than karyotyping. Despite this, aCGH
has yet to be implemented as a routine NHS service. One significant obstacle is the perception that the technology is prohibitively
expensive for most standard NHS clinical cytogenetics laboratories. To address this, we investigated the cost-effectiveness
of aCGH versus standard cytogenetic analysis for diagnosing idiopathic learning disability (ILD) in the NHS. Cost data from
four participating genetics centres were collected and analysed. In a single test comparison, the average cost of aCGH was
£442 and the average cost of karyotyping was £117 with array costs contributing most to the cost difference. This difference
was not a key barrier when the context of follow up diagnostic tests was considered. Indeed, in a hypothetical cohort of 100 ILD
children, aCGH was found to cost less per diagnosis (£3,118) than a karyotyping and multi-telomere FISH approach (£4,957).
We conclude that testing for genomic imbalances in ILD using microarray technology is likely to be cost-effective because
long-term savings can be made regardless of a positive (diagnosis) or negative result. Earlier diagnoses save costs of additional
diagnostic tests. Negative results are cost-effective in minimising follow-up test choice. The use of aCGH in routine clinical
practice warrants serious consideration by healthcare providers.
Copyright statement The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive
licence (or non exclusive for government employees) on a worldwide basis to the BMJ Publishing Group Ltd, and its Licensees
to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and to exploit all subsidiary
rights, as set out in our licence (bmj.com/advice/copyright.shtml).
Authorship The authors included on this paper fulfil the criteria of authorship and no one who fulfils the criteria has been excluded
from authorship. The authors made a substantial contribution to the conception, design, analysis and interpretation of data.
They were involved in drafting the article or revising it critically for important intellectual content and approving the
version to be published.
Contributorship Sarah Wordsworth (Guarantor): Planning, conducting and reporting work, interpretation of data, drafting and revising article.
James Buchanan: Conducting and reporting work, interpretation of data, revising article.
Regina Regan: Completing costing questionnaire, providing protocol details, other costing information, interpretation of data,
information about learning disability and genome imbalance and revising article.
Val Davison: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting
article.
Kim Smith: Completing costing questionnaire, providing protocol details, drafting article.
Sara Dyer: Completing costing questionnaire and providing protocol details.
Carolyn Campbell: Completing costing questionnaire and providing protocol details.
Edward Blair: Critical appraisal of article for clinical content and revising article.
Eddy Maher: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting
article.
Jenny Taylor: Planning and facilitating work between centres. Drafting and revising article.
Samantha JL Knight: Completing costing questionnaire, providing protocol details, other costing information, interpretation
of data, providing information about learning disability and genome imbalance, drafting and revising article.
Jenny Taylor and Samantha JL Knight contributed equally to the work presented. 相似文献
58.
Herdís G. R. Steinsdóttir Eddy Gómez-Ramírez Snehit Mhatre Clemens Schauberger Anthony D. Bertagnolli Zoe A. Pratte Frank J. Stewart Bo Thamdrup Laura A. Bristow 《Environmental microbiology》2022,24(5):2361-2379
Coastal waters are a major source of marine methane to the atmosphere. Particularly high concentrations of this potent greenhouse gas are found in anoxic waters, but it remains unclear if and to what extent anaerobic methanotrophs mitigate the methane flux. Here we investigate the long-term dynamics in methanotrophic activity and the methanotroph community in the coastal oxygen minimum zone (OMZ) of Golfo Dulce, Costa Rica, combining biogeochemical analyses, experimental incubations and 16S rRNA gene sequencing over 3 consecutive years. Our results demonstrate a stable redox zonation across the years with high concentrations of methane (up to 1.7 μmol L−1) in anoxic bottom waters. However, we also measured high activities of anaerobic methane oxidation in the OMZ core (rate constant, k, averaging 30 yr−1 in 2018 and 8 yr−1 in 2019–2020). The OPU3 and Deep Sea-1 clades of the Methylococcales were implicated as conveyors of the activity, peaking in relative abundance 5–25 m below the oxic–anoxic interface and in the deep anoxic water respectively. Although their genetic capacity for anaerobic methane oxidation remains unexplored, their sustained high relative abundance indicates an adaptation of these clades to the anoxic, methane-rich OMZ environment, allowing them to play major roles in mitigating methane fluxes. 相似文献
59.
60.
This study was designed to determine whether significant differences in saturation levels existed among patients with aspiration and patients without and wether pulse oximetry can reliably detect aspiration in patients with dysphagia. We also examined the effects of gender and disease (neurologic versus non neurologic) on saturation levels. We studied 38 patients. They all underwent a videofluoroscopic study of swallowing (VFSS). Twenty patients aspirated on videofluoroscopic study of swallowing: ten patients were solid aspirators, ten patients were liquid aspirators. In each group (liquid aspirators, solid aspirators or non aspirators) we found no significant difference in saturation levels. We found however a significant difference in saturation levels between each group before, during and after videofluoroscopic study of swallowing. Both gender and disease had an effect on saturation levels. We conclude that pulse oximetry can not serve as a screening tool for detection of aspiration as saturation levels are dependent on many factors. Therefore one can not reliably predict aspiration with a single saturation screening. 相似文献